From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id CA024C433FF for ; Thu, 8 Aug 2019 23:48:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A16BD21743 for ; Thu, 8 Aug 2019 23:48:57 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=nvidia.com header.i=@nvidia.com header.b="DiIm8SbQ" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2405065AbfHHXsw (ORCPT ); Thu, 8 Aug 2019 19:48:52 -0400 Received: from hqemgate16.nvidia.com ([216.228.121.65]:17844 "EHLO hqemgate16.nvidia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2404850AbfHHXrF (ORCPT ); Thu, 8 Aug 2019 19:47:05 -0400 Received: from hqpgpgate102.nvidia.com (Not Verified[216.228.121.13]) by hqemgate16.nvidia.com (using TLS: TLSv1.2, DES-CBC3-SHA) id ; Thu, 08 Aug 2019 16:47:06 -0700 Received: from hqmail.nvidia.com ([172.20.161.6]) by hqpgpgate102.nvidia.com (PGP Universal service); Thu, 08 Aug 2019 16:47:04 -0700 X-PGP-Universal: processed; by hqpgpgate102.nvidia.com on Thu, 08 Aug 2019 16:47:04 -0700 Received: from HQMAIL105.nvidia.com (172.20.187.12) by HQMAIL101.nvidia.com (172.20.187.10) with Microsoft SMTP Server (TLS) id 15.0.1473.3; Thu, 8 Aug 2019 23:47:04 +0000 Received: from hqnvemgw01.nvidia.com (172.20.150.20) by HQMAIL105.nvidia.com (172.20.187.12) with Microsoft SMTP Server (TLS) id 15.0.1473.3 via Frontend Transport; Thu, 8 Aug 2019 23:47:04 +0000 Received: from skomatineni-linux.nvidia.com (Not Verified[10.110.103.110]) by hqnvemgw01.nvidia.com with Trustwave SEG (v7,5,8,10121) id ; Thu, 08 Aug 2019 16:47:04 -0700 From: Sowjanya Komatineni To: , , , , , , , CC: , , , , , , , , , , , , , , , , , , Subject: [PATCH v8 12/21] cpufreq: tegra124: Add suspend and resume support Date: Thu, 8 Aug 2019 16:46:51 -0700 Message-ID: <1565308020-31952-13-git-send-email-skomatineni@nvidia.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1565308020-31952-1-git-send-email-skomatineni@nvidia.com> References: <1565308020-31952-1-git-send-email-skomatineni@nvidia.com> X-NVConfidentiality: public MIME-Version: 1.0 Content-Type: text/plain DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nvidia.com; s=n1; t=1565308026; bh=F15XAU7jizr+feJ2UEN0D8nDDnwfPQ1DdVDP+ne0krg=; h=X-PGP-Universal:From:To:CC:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:X-NVConfidentiality:MIME-Version: Content-Type; b=DiIm8SbQO+GNmP8myF8kslsguetVqPKnpVAGIIK8X0P/mhUg5v00X4lLDKSCFG2hl a6/nrSE0ULtxxsNk4Sicyk3gCwn+RlCv0YM7ZF26DIatJlmUMgaAZuf6XT2YvwqMN+ aM4DCyOsTo10juYViiLOfVJXInAzKEWVCzI9XI4AOm+RKEbOMfQ/mJrkrhST3R+WKq TMsKbdY2Zl72C/LcKVYGl0acH72Fzq1OFdxn12dPFy6um7I9cdIDHTF+hWFQRxSDeW nUpad2gJbphmoWHDkDcLsknr4cY9JAcaJObk2SwPSM8anyXT1L9Z0J9ZpDzrqZ+wVo kRr78/b3q0Bhg== Sender: linux-gpio-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-gpio@vger.kernel.org This patch adds suspend and resume pm ops for cpufreq driver. PLLP is the safe clock source for CPU during system suspend and resume as PLLP rate is below the CPU Fmax at Vmin. CPUFreq driver suspend switches the CPU clock source to PLLP and disables the DFLL clock. During system resume, warmboot code powers up the CPU with PLLP clock source. So CPUFreq driver resume enabled DFLL clock and switches CPU back to DFLL clock source. Acked-by: Viresh Kumar Reviewed-by: Dmitry Osipenko Signed-off-by: Sowjanya Komatineni --- drivers/cpufreq/tegra124-cpufreq.c | 60 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 60 insertions(+) diff --git a/drivers/cpufreq/tegra124-cpufreq.c b/drivers/cpufreq/tegra124-cpufreq.c index 4f0c637b3b49..e979a3370988 100644 --- a/drivers/cpufreq/tegra124-cpufreq.c +++ b/drivers/cpufreq/tegra124-cpufreq.c @@ -6,6 +6,7 @@ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include +#include #include #include #include @@ -128,8 +129,67 @@ static int tegra124_cpufreq_probe(struct platform_device *pdev) return ret; } +static int __maybe_unused tegra124_cpufreq_suspend(struct device *dev) +{ + struct tegra124_cpufreq_priv *priv = dev_get_drvdata(dev); + int err; + + /* + * PLLP rate 408Mhz is below the CPU Fmax at Vmin and is safe to + * use during suspend and resume. So, switch the CPU clock source + * to PLLP and disable DFLL. + */ + err = clk_set_parent(priv->cpu_clk, priv->pllp_clk); + if (err < 0) { + dev_err(dev, "failed to reparent to PLLP: %d\n", err); + return err; + } + + /* disable DFLL clock */ + clk_disable_unprepare(priv->dfll_clk); + + return 0; +} + +static int __maybe_unused tegra124_cpufreq_resume(struct device *dev) +{ + struct tegra124_cpufreq_priv *priv = dev_get_drvdata(dev); + int err; + + /* + * Warmboot code powers up the CPU with PLLP clock source. + * Enable DFLL clock and switch CPU clock source back to DFLL. + */ + err = clk_prepare_enable(priv->dfll_clk); + if (err < 0) { + dev_err(dev, "failed to enable DFLL clock for CPU: %d\n", err); + goto disable_cpufreq; + } + + err = clk_set_parent(priv->cpu_clk, priv->dfll_clk); + if (err < 0) { + dev_err(dev, "failed to reparent to DFLL clock: %d\n", err); + goto disable_dfll; + } + + return 0; + +disable_dfll: + clk_disable_unprepare(priv->dfll_clk); +disable_cpufreq: + disable_cpufreq(); + + return err; +} + +static const struct dev_pm_ops tegra124_cpufreq_pm_ops = { + SET_SYSTEM_SLEEP_PM_OPS(tegra124_cpufreq_suspend, + tegra124_cpufreq_resume) +}; + static struct platform_driver tegra124_cpufreq_platdrv = { .driver.name = "cpufreq-tegra124", + .driver.pm = &tegra124_cpufreq_pm_ops, .probe = tegra124_cpufreq_probe, }; -- 2.7.4